LU-2093 lod: fall back to RR allocation when QoS fails

[fs/lustre-release.git] / lustre / lod / lod_qos.c

diff --git a/lustre/lod/lod_qos.c b/lustre/lod/lod_qos.c
index 28e31e4..2a70c09 100644 (file)
--- a/lustre/lod/lod_qos.c
+++ b/lustre/lod/lod_qos.c
@@ -699,6 +699,10 @@ static int lod_alloc_rr(const struct lu_env *env, struct lod_object *lo,
        if (rc)
                GOTO(out, rc);
 
+       rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr);
+       if (rc)
+               GOTO(out, rc);
+
        if (--lqr->lqr_start_count <= 0) {
                lqr->lqr_start_idx = cfs_rand() % osts->op_count;
                lqr->lqr_start_count =
@@ -1030,6 +1034,10 @@ static int lod_alloc_qos(const struct lu_env *env, struct lod_object *lo,
        if (rc)
                GOTO(out, rc);
 
+       rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr);
+       if (rc)
+               GOTO(out, rc);
+
        good_osts = 0;
        /* Find all the OSTs that are valid stripe candidates */
        for (i = 0; i < osts->op_count; i++) {
@@ -1140,27 +1148,42 @@ static int lod_alloc_qos(const struct lu_env *env, struct lod_object *lo,
                         */
                        if (lod_qos_is_ost_used(env, idx, nfound))
                                continue;
+                       lod_qos_ost_in_use(env, nfound, idx);
 
                        o = lod_qos_declare_object_on(env, m, idx, th);
                        if (IS_ERR(o)) {
-                               CERROR("can't declare new object on #%u: %d\n",
-                                      idx, (int) PTR_ERR(o));
+                               QOS_DEBUG("can't declare object on #%u: %d\n",
+                                         idx, (int) PTR_ERR(o));
                                continue;
                        }
-                       lod_qos_ost_in_use(env, nfound, idx);
                        lo->ldo_stripe[nfound++] = o;
                        lod_qos_used(m, osts, idx, &total_weight);
                        rc = 0;
                        break;
                }
+       }
 
-               /* should never satisfy below condition */
-               if (rc) {
-                       CERROR("Didn't find any OSTs?\n");
-                       break;
+       if (unlikely(nfound != stripe_cnt)) {
+               /*
+                * when the decision to use weighted algorithm was made
+                * we had enough appropriate OSPs, but this state can
+                * change anytime (no space on OST, broken connection, etc)
+                * so it's possible OSP won't be able to provide us with
+                * an object due to just changed state
+                */
+               LCONSOLE_INFO("wanted %d, found %d\n", stripe_cnt, nfound);
+               for (i = 0; i < nfound; i++) {
+                       LASSERT(lo->ldo_stripe[i]);
+                       lu_object_put(env, &lo->ldo_stripe[i]->do_lu);
+                       lo->ldo_stripe[i] = NULL;
                }
+
+               /* makes sense to rebalance next time */
+               m->lod_qos.lq_dirty = 1;
+               m->lod_qos.lq_same_space = 0;
+
+               rc = -EAGAIN;
        }
-       LASSERT(nfound == stripe_cnt);
 
 out:
        cfs_up_write(&m->lod_qos.lq_rw_sem);
@@ -1376,10 +1399,6 @@ int lod_qos_prep_create(const struct lu_env *env, struct lod_object *lo,
                        GOTO(out, rc = -ENOMEM);
                lo->ldo_stripes_allocated = lo->ldo_stripenr;
 
-               rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr);
-               if (rc)
-                       GOTO(out, rc);
-
                lod_getref(d);
                /* XXX: support for non-0 files w/o objects */
                if (lo->ldo_def_stripe_offset >= d->lod_desc.ld_tgt_count) {